1. Field of the Invention
The present invention relates generally to controllers for allocating energy consumption on a priority basis and more particularly to an energy controller designed to be adaptable to conventional housing or office buildings.
2. Description of the Prior Art
Power supply companies have traditionally billed industrial users based upon a demand billing rate. Such a rate structure is desirable since the power supply company must be capable of meeting peak supply demands by it's various industrial users. Therefore, it is highly desirable to bill the industrial users based upon their highest demand for generally a fifteen minute interval during a given month. While industry has responded with a variety of approaches to substantially reduce the occurrence of a peak demand level during a given month through use of a variety of energy allocation devices, none of the above prior art approaches have been found suitable for private residential use.
Power supply companies have been billing residential consumers based upon what is commonly termed the "rate" basis. The "rate" basis for computing power consumption is based upon the concept that the residential user should pay for the power actually used. The philosophy behind this approach being that most consumers live within a predetermined amount of average power consumption so that the power supply company can properly allocate the power requirements to the residential community. Power supply companies in various states are commencing to adopt the demand rate structure for residential users. While some energy controllers designed for industrial applications have been modified for the residential environment, such controllers severely inconvenience the public since as power consumption increases, selected appliances, lights, heaters, and/or outlets are deactivated on a priority basis. Such priority shutoffs often irate consumers and are often disconnected.
The energy demand controller of the present invention meets this new market by providing a low-cost approach for providing energy priority and allocation in order to prevent peak energy uses from occurring. The apparatus and method taught by the present invention for the first time provides a new and novel approach to heating zones or rooms within the building or house by sequentially turning on the heater in each zone for a predetermined length of time, usually one second, thereby preventing the simultaneous activation of all heaters in all zones at the same time. Currently, zone heating occurs at a purely random basis dependent upon the temperature in the particular zone and whether that temperature is at the desired level. The energy demand controller of the present invention turns on the first zone heater for one second etc. then returns back to the first zone and turns it on for an additional second. In the event that the inhabitant of the house or building desires to use an appliance, a special override feature is provided so that while the appliance is being used, no cyclic heating in the zones occurs.
The energy demand controller of the present invention also functions when the temperature in each of the zones falls below a predetermined low value by providing the feature of activating the heater within the zone on a fulltime basis until the temperature rises to a predetermined range. In the event that a certain given number of zones require such full time heating, the energy controller of the present invention prevents any appliance from being activated until the room temperature is brought up to within operational range in a predetermined number of zones. This situation usually occurs when the house is cold and the heat is turned on initially or when the outside temperature is very low. The house must obtain the desired range of living temperatures before the appliances can be activated.
Of course, during normal operation, the heat in the room is at the desired temperature and the energy demand controller will continually interrogate the temperature difference between the actual temperature and the desired temperature for each zone but no heating will occur. In that mode, appliances can be safely utilized. It is only when the temperature within a particular zone commences to drop that priority action occurs in the allocation of power consumption.